I did an antibacterial activity of lime peel. I use ethyl acetate as the solvent. The ratio is 1:4. The method of extraction is maceration for 3 days. I stir it everyday. After the 3 days of maceration, next i filter it with whatman filter papers and evaporate it in 40 degree until the extract becomes thicker. I put it in oven 40 degree for 24 hours to make sure all of the solvent has evaporated. The next day i put it in the refrigerator.

I used the extract to test the antibacterial activity with Staphylococcus aureus. I've done it before and it has an inhibition zone, but this time it doesn't have any inhibition zone.. It does have but only a real small inhibition zone (7mm). But according to the journals that I've read, they get like 20-25mm inhibition zone and i wonder what's wrong with my research. I'm still looking the problems, that's why i come here to look for an expert.

Thank you so much